2, Argonne National Laboratory, Argonne, Illinois, United States
Components of any system, from suspension bridges to computer chips, must be designed to withstand the stresses they will experience. At the macroscopic scale, stress is well understood and methods for characterizing these stresses using neutron and high-energy X-ray diffraction are well established. Microscopic stresses within complex microstructures and devices are less well understood, largely because methods for characterizing stresses at micrometer and sub-micrometer length scales are lacking. As just one example, it has been estimated that thermo-mechanically induced stress is responsible for approximately 65% of all microelectronic device failures, but almost all studies of these stresses use finite element simulations with no direct experimental validation. Recent advances in synchrotron X-ray techniques by researchers at the National Institute of Standards and Technology and the Advanced Photon Source (APS) at Argonne National Laboratory have provided an unprecedented capability for probing phases, microstructure, and full strain/strain tensors with micrometer, and even submicrometer, spatial resolution within complex real-world materials. An overview of these microbeam measurement capabilities at beamline 34ID-E at the APS will be presented, along with example studies of microscopic stresses within microelectronics, plastically deformed metals, and additive manufactured metal components. Finally, prospects for future developments in this area will be described.